Now they’re teaming up with conservationists to put a new twist on another ancient cry – “Whales ho!’’

The sport of sailboat racing and nonprofit groups are floating new guidelines aimed at increasing awareness of the majestic mammals and reducing potentially fatal collisions with endangered North Atlantic right whales and other species.

The guidelines were just incorporated into two major open-ocean sailing competitions – the Marblehead to Halifax race starting Sunday from Massachusetts and stretching to Nova Scotia; and last week’s Vineyard Cup regatta off Martha’s Vineyard.

Race crews for both events were given customized information telling them where whales were likely to congregate along their courses.

Collisions can be rough on competitors – and crippling or deadly for whales.

Marine scientists said last month that six rare right whales died in Canadian waters in the past few weeks. Preliminary investigations suggest collisions with vessels likely were to blame for at least two of those deaths, and another whale died after becoming entangled in fishing gear.

Federal law requires all boats to slow down in shipping channels known to be frequented by whales. But that doesn’t always help animals in the open Atlantic, where racing sailboats are moving fast.

“In the last year, at least two sailors in open ocean races collided with whales during the competition and had to be rescued,’’ said Monica Pepe, policy manager for Whale and Dolphin Conservation, a conservation and research organization based in Plymouth, Massachusetts.

“We’re hopeful that the information we’ve shared will help to keep everyone safe and help sailors know what to look for while also encouraging them to report any sightings of whales in distress along their courses,’’ Pepe said. Organizers hope the America’s Cup and other major races eventually incorporate it, she said.

Sailors are given tips to navigate safely around whales; contact information for authorities in case they see a whale or sea turtle that’s entangled or otherwise in distress; and reminders on keeping debris out of the ocean. It’s tailored to each race; course maps are overlaid with any nearby whale habitat.

The Audubon Society of Rhode Island and the New Bedford Whaling Museum helped Pepe’s group launch the initiative, which has been dubbed “Sharing the Seas.”

The joint effort also involved US Sailing, the sport’s national governing body, and Sailors for the Sea, a Newport, Rhode Island-based group that promotes responsible ocean stewardship among sailors.

Anne Coulombe, co-director of the Marblehead to Halifax race, calls the information “critical to the safety of our racing crews as well as to marine life.’’

“We thought it essential to include it in our skipper’s packets,’’ she said.